Glass



Patented Sept. 23, 1930 UNITED STATES PATENT? OFFICE BERNARD LONG, OFPARIS, FRANCE, ASS IGNOR TO SOCIETE ANONYME DES MANUFAO- TUBES DES GLACES' ET PRODUITS CHIMIQUES DE 01: PARIS, FRANCE No Drawing. Originalapplication filed January 12,1926, Serial No. 80,839, and in FranceJanuary 10,

GLASS SAINT-GOBAIN, CHAUNY ET CIBEY,

1927. Divided and-this application filed October 18, 1927. Serial No.228,050.

light. I have iscovered'that this change of tint in glasses of this typeis due to the action of shorter wave lengths contained in the sunlightincausing new combinations of oxygen in the glass with metallic basesfound therein, such as iron, manganese and selenium, and have discoveredthat this can be avoided by incorporating in the glass small quantitiesof ingredients tending to absorb the oxygenliberated by such short wavelengths without causing coloration. To carry out my invention I proposeto incorporate in a glass of the character described a small quantity ofa metallic oxide having the property of absorbing oxygen without theformation of a glass colorin oxide.

Consider a well known glass such as the following Na O 15.5 OaO 12.5This glass is liable to color changes under the conditions above stated.1 Y

- cent of oxide 0 geti'c'in its action in absorbing than the lead oxide.The substitution'in question ma be made by replacing a given percenta eof the silica, alkali or base of the above a? ass with ment thereinwhich is efi'ected by waves of short lengths and containing asubstantial quantity but not over 2% of titanium oxide.

. 2. -'A soda-lime glass having a metallic ele ment therein which isefiected by waves of short-length and containing not over 2% of titaniumoxide, the said oxide being present in a quantity suflicient to absorboxygen liberated'in the glass and tending to cause discoloration.

In testimony whereof I hereunto ailix my signature.

' BERNARD LONG.

- per cent, the titanium oxide being more eneran equal percentage of thelead or titanium oxide.

This application is a division of my rior application filed January 12,1926 'Seri No. 80,839, which on May- 15, 1928 issued into Patent No.1,669,908, claiming the use of oxide of lead for the purposes hereinspecified.

Having thus described my invention what I claim and desire to secure byLetters Patcut is 1. A soda lime glas having a metallic eletoo

